Please help me narrow down my searching! Family holiday, 2 adults, 2 primary aged kids. To go either May half term or early summer. We are looking for somewhere to experience mountain scenery, lakes and rivers, nature, that is accessible. We'd like to feel slightly adventurous but secretly it's not all that adventurous, i.e. not risky. We want to use trains and buses, not drive. One base or multiple. Any suggestions?